With over 70% of all attacks now carried out over the web application level, organisations need every help they can get in making their systems secure. Web application firewalls are deployed to establish an external security layer that increases security, detects, and prevents attacks before they reach web applications.

HTTP Traffic Logging

Web servers are typically well-equipped to log traffic in a form useful for marketing analyses, but fall short when it comes to logging of traffic to web applications. In particular, most are not capable of logging the request bodies. Your adversaries know this, and that is why most attacks are now carried out via POST requests, rendering your systems blind.

ModSecurity makes full HTTP transaction logging possible, allowing complete requests and responses to be logged. Its logging facilities also allow fine-grained decisions to be made about exactly what is logged and when, ensure only the relevant data is recorded.

Real-Time Monitoring and Attack Detection

In addition to providing logging facilities, ModSecurity can monitor the HTTP traffic in real time in order to detect attacks. In this case ModSecurity operates as a web intrusion detection tool, allowing you to react to suspicious events that take place at your web systems.

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You don't need to be a genius to debug a pf.conf firewall ruleset, you just need the guts to run tcpdump

As request, barti, it would be courteous to others to at least provide a short description of why you post links to this site. Some would consider blindly going to an unknown site to be both insecure & a ruse.

While I can understand brevity, the fact that you don't provide any explanation whatsoever makes me believe if it wasn't important enough to you to provide even a minimal description, I shouldn't bother finding out what is on the other side of the link.